Study: Too Much Folic Acid ‘Increases Autism Risk’

The benefits of adding extra folic acid to your diet before and during pregnancy are well documented, but a new study suggests that adding too much could be detrimental to your baby's health.  Researchers at Johns Hopkins University Bloomberg School of Public Health found that if a new mother records a very high folate level (more than four times what's considered normal) directly after giving birth, the risk that her child will develop an autism spectrum disorder doubles. After analysing data from 1,391 mother-child pairs, doctors also discovered that new mums with very high vitamin B12 levels have triple the risk of their baby developing an autism spectrum disorder. If both levels (folate and B12) are considerably higher than recommended, the risk is more than 17 times higher than normal.

"Adequate supplementation is protective: That's still the story with folic acid," says one of the study's senior authors M. Daniele Fallin, PhD, director of the Bloomberg School's Wendy Klag Center for Autism and Developmental Disabilities. "We have long known that a folate deficiency in pregnant mothers is detrimental to her child's development. But what this tells us is that excessive amounts may also cause harm. We must aim for optimal levels of this important nutrient."

In recent years there has been an increase in the numbers of babies born with neural tube defects. As a result, doctors have been reissuing their advice that all women of child-bearing age should supplement with folic acid, even where conception is not being planned.

"This research suggests that this could be the case of too much of a good thing," added study lead author Ramkripa Raghavan, MPH, MSc. "We tell women to be sure to get folate early in pregnancy. What we need to figure out now is whether there should be additional recommendations about just what an optimal dose is throughout pregnancy."

So what's a pregnant girl to do? Like almost everything else, the best thing is to take an 'everything in  moderation' approach. For more on the best supplements and how to use them, click here.